That chatter about team togetherness and chemistry established a month before training camp is just that, chatter. It was wishful thinking to believe the Celtics would start the season with midseason-like cohesion because they seemingly want to make matters difficult for themselves.

The problem is more profound after their 106-100 home loss to Philadelphia on Friday. The Celtics are essentially a 2½-man team, relying far too heavily on 18-year veteran Kevin Garnett and the 40-plus minute production of Rajon Rondo, who has no issue churning out assists but can’t stop dribble penetration for prolonged stretches.

The half is Paul Pierce, who led the Celtics with a misleading 24 points but he looked ragged, slow, and erratic for most of the contest, scoring a handful of points when his team’s fate was decided.

Of the other eight players in the rotation, the Celtics aren’t getting all that much. Jason Terry is coming through with points in bunches, but the Celtics are seemingly always behind when he gets hot. Courtney Lee is playing the first half and watching from the bench in crunch time. He scored his 6 points in the first 6:05 of the game and was a nonfactor after­ward.

Jeff Green, considered the team’s X factor, is averaging just 7 points and 2.4 rebounds. He is admittedly struggling, carrying the same passive game he brought to Boston from Oklahoma City nearly two years ago. And he’s caught in a tough spot because coach Doc Rivers is not playing him because of a lack of production, but he can’t get going if he isn’t on the court.

And finally the idea of starting Jared Sullinger seemed like a bright one in training camp but the Celtics need more than 4 points and 4.6 rebounds from their power forward. It may be time to return to Brandon Bass permanently. Rivers said passionately that starting lineups don’t matter to him, it’s about minutes, and that is his predicament.

He has to limit Garnett’s minutes, but the Celtics are a minus-29 with Garnett on the bench, meaning the other team generally makes a run when KG gets rest. Rondo can’t be the Celtics’ primary scorer with Garnett on the bench. Although his offensive arsenal is improving, opposing teams are daring Rondo to shoot and create for himself.

That leaves all the pressure on Pierce, who is off to another tortoise-like start, meaning his lift is nonexistent, he is looking for foul calls that aren’t there and the jumper is rusty. Pierce is being saved by his 3-point shot. On 2-pointers, Pierce is 19 of 54, a sign his game has yet to arrive in time for the winter.

Rivers is visibly frustrated, although he is seeing progress. The Celtics shot 58.3 percent after halftime and held the 76ers to 45.9 shooting in the final two quarters, which regrettably is progress. But the Celtics need someone besides Garnett to produce.

As usual, the Celtics are easing into the season and the Miami Heat are practically laughing at their struggles. The Celtics hardly resemble a playoff team, let alone an Eastern Conference contender. They have not beaten anyone besides the winless Washington Wizards, meaning their two razor-thin victories are hollow.

A statement is needed and Garnett can’t be the one to make it.

“We’ve got to put the work in in practice to figure out the second unit,” Pierce said of how to respond with Garnett on the bench. “But that’s going to come. Our identity is going to be a defensive team first and we’ve got talent offensively to where we think it will come together. We’ve got to do a better job of sharing the ball, making the extra passes, but the main concern is the transition defense and rebounding the ball.

“I understand that it’s a process, we’re going five games in. We’re still building even though we lost today, there’s some positive things we can build from that. It’s still a long season. It’s still some things we got to get together mentally, maybe a road trip like this one against two pretty good teams will solve it.”

The “things will work themselves out” is one method to take and another is to attack the issue and expedite the chemistry process. The Celtics were testy after the game, unsure if progress is actually occurring 10 days into the season.

Arguably the Celtics best game of the season was their first, the 120-107 loss to the Heat. That was nearly two weeks ago and growth has been difficult to determine since then. The veterans have to respond. The newcomers can no longer be passive and Garnett, well he just has to maintain his high level and hope his teammates follow suit.

Right now, they’re not. He is withstanding too much pressure and eventually his 36-year-old enthusiasm will wilt.

They have to preserve his production for the later months, meaning someone else has to wrestle the fate and responsibility of this team from him.

Right now, the other 12 players are content to watch Garnett navigate against the rest of the NBA, which is taking pleasure in the Celtics’ stupor.

“Kevin does a great job of talking [on defense], just follow the leader,” Rondo said. “It seems that it’s just a matter of guys just don’t talk. For us to win, I think we need guys to come out their comfort zone and do something that they’re not comfortable with.

“We got the right guys. We got the right mind-set, it’s just a matter of doing it.”